Modern mobile communications tends to provide various services to users. At present, the public security department of the United States has taken LTE network as a basic communication network for its public security telecommunication service. Proximity based service (shortened as ProSe) between/among UEs is an important component for the public security telecommunications, including ProSe direct discovery among UEs and ProSe direct communication among UEs. The ProSe discovery among UEs may forms a basis for direct communication among UEs. It may sense whether there is a friend user nearby and prompt the user with a subsequent operation. In the public security field, it helps public security department personnel to take commands and cooperate with each other in a specific scenario and further ensures the security via secrecy schemes. More flexible applications are found in the business field. Especially, it can support rapid construction of a social network within an area, e.g., discovery of nearby users with the same interest or nearby push of commercial advertisement.
FIG. 1 shows a schematic diagram of a system structure for supporting UE access control. In FIG. 1, User Equipment (UE) 101 is a terminal device supporting D2D proximity service. Evolved UMTS Terrestrial Radio Access Network (E-UTRAN) 102 is a radio access network, wherein it includes a base station (eNodeB) providing an interface for accessing radio network for the UE and may implement D2D service resource configuration for the UE 101. Mobility Management Entity (MME) 103 is responsible for managing mobile context, session context and security information of the UE. Home Subscriber Server (HSS) 104 is a home subscriber system of the UE, responsible for storing user information such as current location of the UE, address of a serving node, user security information and packet data context of the UE, and for storing user access service subscription information. ProSe Function 105 is responsible for storing user information including the UE currently used by a ProSe user, a user identifier for being discovered, user ProSe security information and user ProSe context.
During a D2D service (also referred to as proximity service, shortened as ProSe), there are a UE announcing signals and a UE monitoring signals. The UE monitoring signals identify information from a nearby UE or user through monitoring information announced by a nearby UE announcing signals. In the case of being in the network coverage, radio resources for D2D service of the UE are allocated by the network. A shared allocation mechanism may be utilized, i.e., common radio resources are allocated to all UEs or a group of UEs and the UEs or the UEs in the group compete for the radio resources. It is also possible to use a dedicate allocation mechanism, i.e., dedicate resources are allocated to each UE.
There are the following problems in the current D2D direct discovery and D2D direct communication.
Problem 1: in the network coverage, an application of the UE may frequently revoke the D2D function of the UE to request different D2D services. Each D2D request requires an authentication by the ProSe Function, which brings heavy signaling overhead to the network.
Problem 2: in the network coverage, the UE-specific D2D resources have to be scheduled and allocated by the base station. When the UE initiates the resource allocation to the base station, the base station does not know whether the D2D service is authorized for the D2D service(s).